Aralkylamine dehydrogenase (azurin) (AADH)

Aralkylamine dehydrogenase (AADH), specifically aralkylamine dehydrogenase (azurin), is a quinoprotein enzyme primarily found in various bacterial species, including Alcaligenes faecalis and Pseudomonas aeruginosa [1, 41]. It catalyzes the oxidative deamination of aralkylamines, such as tyramine, phenethylamine, and dopamine, into their corresponding aldehydes, utilizing azurin or other electron-transfer proteins as acceptors [1, 32]. The enzyme is a heterodimer consisting of heavy and light subunits and is characterized by the presence of a tryptophan tryptophylquinone (TTQ) cofactor, which is essential for its catalytic mechanism [1, 36]. In the field of drug discovery, AADH is recognized as a potential antimicrobial target, as its inhibition can disrupt bacterial nitrogen metabolism and amine catabolism [41, 56]. While it is not present in humans—where similar reactions are performed by monoamine oxidases (MAOs)—it is frequently included in bioactivity prediction models to screen for novel inhibitors [29, 30]. Research into AADH inhibitors, such as isoniazid derivatives and other hydrazine-based agents, aims to develop selective antimicrobial therapies that avoid cross-reactivity with human amine-metabolizing enzymes [30, 31].

Other names

Aromatic amine dehydrogenaseArylamine dehydrogenaseTyramine dehydrogenaseAralkylamine:azurin oxidoreductase (deaminating)

Inhibition of the oxidative deamination of aralkylamines, disrupting bacterial nitrogen acquisition and amine detoxification pathways.